1. Field of the Invention
This invention relates to a motion controlling apparatus and a motion controlling method for a legged mobile robot having at least a plural number of mobile legs. This invention especially relates to a motion controlling apparatus and a motion controlling method for a legged mobile robot which may be presupposed to be used in a large variety of different environments.
More particularly, the present invention relates to a motion controlling apparatus and a motion controlling method in which the robot motion on the occasion of occurrence of a reflection type error is guaranteed. More specifically, the invention relates to a motion controlling apparatus and a motion controlling method in which the processing for avoiding the occurrence of the reflective error may be carried out autonomously.
This application claims the priority of the Japanese Patent Application No. 2002-298355 filed on Oct. 11, 2002, the entirety of which is incorporated by reference herein.
2. Description of Related Art
A mechanical apparatus for performing motions simulating the motions of the human being, with the use of electrical or magnetic operations, is termed a “robot”. The etymology of the term robot is said to be “ROBOTA” (slave machine) of the Slavic language. In Japan, the robots started to be used towards the end of the 1960s. Most of these robots used were industrial robots, such as manipulators or transporting robots, aimed to automate or perform unmanned tasks in plant operations.
In recent years, researches and developments in legged mobile robots, simulating the bodily mechanism and motions of an animal which is erected and walks on two feet, such as human beings or monkeys, are progressing, such that there are good prospects for practical utilization of these robot types. The motion system by legs, erected and walking on two legs, is unstable as compared to the crawler type system or the system walking on four or six legs, and hence is difficult to control as to posture or walking. However, the motion system by legs, erected and walking on two legs, is favorable in such respects that it is able to cope with a work route presenting an irregular walking surface, such as non-leveled terrain or obstacles or a non-continuous walking surface, such as staircase or ladder, thereby achieving more flexible motion operations.
In the meantime, the legged mobile robot, regenerating the mechanism of the living body or motions of the human beings, is termed a “humanoid” or a “humanoid robot”. The humanoid robot is able to support the human life, that is to support human activities, in various aspects of our everyday life, such as in our living environments.
The major portions of the work space or the living space of the human beings are tailored to the bodily mechanism and the behavior patterns of the human beings, which are erect and walk on two feet, and there are many obstacles to motions of the state-of-the-art mechanical system, having wheeled or the like driving device as motion means. Thus, in order for the mechanical system, that is, the robot, to take the place of the human beings in a large variety of tasks or operations and to adapt itself to the living environment of the human beings, it is desirable that the possible range of motion of the robot is substantially the same as that of the human beings. This accounts for the great general expectation towards practical utilization of legged mobile robots.
The legged mobile robot of a large height is presupposed to be used on terrains of a variety of different conditions, including both level and non-level terrains, such that many use environments of the robot may depart from normal use conditions that may be managed by the control system of the robot body. Thus, the possibility of occurrence of an unforeseen reflection type error is higher with the legged mobile robot than in other mechanical devices. It is therefore desirable for the robot to perform the processing for avoiding a variety of errors autonomously.